/**
 * @class Ext.chart.axis.Category
 * @extends Ext.chart.axis.Axis
 *
 * A type of axis that displays items in categories. This axis is generally used to
 * display categorical information like names of items, month names, quarters, etc.
 * but no quantitative values. For that other type of information <em>Number</em>
 * axis are more suitable.
 *
 * As with other axis you can set the position of the axis and its title. For example:
 *
 * {@img Ext.chart.axis.Category/Ext.chart.axis.Category.png Ext.chart.axis.Category chart axis}
 *
 *     var store = new Ext.data.JsonStore({
 *         fields: ['name', 'data1', 'data2', 'data3', 'data4', 'data5'],
 *         data: [
 *             {'name':'metric one', 'data1':10, 'data2':12, 'data3':14, 'data4':8, 'data5':13},
 *             {'name':'metric two', 'data1':7, 'data2':8, 'data3':16, 'data4':10, 'data5':3},
 *             {'name':'metric three', 'data1':5, 'data2':2, 'data3':14, 'data4':12, 'data5':7},
 *             {'name':'metric four', 'data1':2, 'data2':14, 'data3':6, 'data4':1, 'data5':23},
 *             {'name':'metric five', 'data1':27, 'data2':38, 'data3':36, 'data4':13, 'data5':33}                                                
 *         ]
 *     });
 *  
 *     new Ext.chart.Chart({
 *         renderTo: Ext.getBody(),
 *         width: 500,
 *         height: 300,
 *         store: store,
 *         axes: [{
 *             type: 'Numeric',
 *             grid: true,
 *             position: 'left',
 *             fields: ['data1', 'data2', 'data3', 'data4', 'data5'],
 *             title: 'Sample Values',
 *             grid: {
 *                 odd: {
 *                     opacity: 1,
 *                     fill: '#ddd',
 *                     stroke: '#bbb',
 *                     'stroke-width': 1
 *                 }
 *             },
 *             minimum: 0,
 *             adjustMinimumByMajorUnit: false
 *         }, {
 *             type: 'Category',
 *             position: 'bottom',
 *             fields: ['name'],
 *             title: 'Sample Metrics',
 *             grid: true,
 *             label: {
 *                 rotate: {
 *                     degrees: 315
 *                 }
 *             }
 *         }],
 *         series: [{
 *             type: 'area',
 *             highlight: false,
 *             axis: 'left',
 *             xField: 'name',
 *             yField: ['data1', 'data2', 'data3', 'data4', 'data5'],
 *             style: {
 *                 opacity: 0.93
 *             }
 *         }]
 *     });
 *
 * In this example with set the category axis to the bottom of the surface, bound the axis to
 * the <em>name</em> property and set as title <em>Month of the Year</em>.
 */

Ext.define('Ext.chart.axis.Category', {

    extend: 'Ext.chart.axis.Axis',

    type: 'category',

    // TODO(zhangbei): seems not used?
    config: {
        /**
         * @cfg {Array} categoryNames
         * A list of category names to display along this axis.
         */
        categoryNames: null,

        /**
         * @cfg {Boolean} calculateCategoryCount
         * Indicates whether or not to calculate the number of categories (ticks and
         * labels) when there is not enough room to display all labels on the axis.
         * If set to true, the axis will determine the number of categories to plot.
         * If not, all categories will be plotted.
         */
        calculateCategoryCount: false
    },

    // @private creates an array of labels to be used when rendering.
    deduceLabels: function() {
        var me = this,
            chart = me.getChart(),
            store = chart.getStore(),
            fields = Ext.Array.from(me.getFields()),
            ln = fields.length,
            labels = [],
            i;

        store.each(function(record) {
            for (i = 0; i < ln; i++) {
                labels.push(record.get(fields[i]));
            }
        }, this);
        
        this.setLabels(labels);
    },

    calcEnds: function () {
        var count = this.getChart().getStore().getCount();
        return {
            from: 0,
            to: count - 1,
            power: 1,
            step: 1,
            steps: count - 1
        };
    },
    
    // @private calculates labels positions and marker positions for rendering.
    applyData: function() {
        this.callParent();
        this.deduceLabels();
        return this.calcEnds();
    }
});
